From f051f96b73dad5e68500750d2e524acc5b476102 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Wed, 18 Sep 2024 15:59:57 +0200
Subject: [PATCH] Use `Font::ascent` for the logical rect, but
 `FontImpl::ascent` for centering

---
 crates/epaint/src/text/text_layout.rs       | 16 ++++++++++------
 crates/epaint/src/text/text_layout_types.rs |  9 ++++++---
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/crates/epaint/src/text/text_layout.rs b/crates/epaint/src/text/text_layout.rs
index e8aea6108..0dbb40c34 100644
--- a/crates/epaint/src/text/text_layout.rs
+++ b/crates/epaint/src/text/text_layout.rs
@@ -172,7 +172,8 @@ fn layout_section(
                 chr,
                 pos: pos2(paragraph.cursor_x, f32::NAN),
                 size: vec2(glyph_info.advance_width, line_height),
-                ascent: font.ascent(),
+                font_impl_ascent: font_impl.map_or(0.0, |f| f.ascent()),
+                font_ascent: font.ascent(),
                 uv_rect: glyph_info.uv_rect,
                 section_index,
             });
@@ -392,7 +393,8 @@ fn replace_last_glyph_with_overflow_character(
             chr: overflow_character,
             pos: pos2(x, f32::NAN),
             size: vec2(replacement_glyph_info.advance_width, line_height),
-            ascent: font.ascent(),
+            font_impl_ascent: font_impl.map_or(0.0, |f| f.ascent()),
+            font_ascent: font.ascent(),
             uv_rect: replacement_glyph_info.uv_rect,
             section_index,
         });
@@ -404,13 +406,14 @@ fn replace_last_glyph_with_overflow_character(
 
         let x = 0.0; // TODO(emilk): heed paragraph leading_space 😬
 
-        let (_, replacement_glyph_info) = font.font_impl_and_glyph_info(overflow_character);
+        let (font_impl, replacement_glyph_info) = font.font_impl_and_glyph_info(overflow_character);
 
         row.glyphs.push(Glyph {
             chr: overflow_character,
             pos: pos2(x, f32::NAN),
             size: vec2(replacement_glyph_info.advance_width, line_height),
-            ascent: font.ascent(),
+            font_impl_ascent: font_impl.map_or(0.0, |f| f.ascent()),
+            font_ascent: font.ascent(),
             uv_rect: replacement_glyph_info.uv_rect,
             section_index,
         });
@@ -596,8 +599,9 @@ fn galley_from_rows(
         for glyph in &mut row.glyphs {
             let format = &job.sections[glyph.section_index as usize].format;
 
-            glyph.pos.y =
-                cursor_y + glyph.ascent + format.valign.to_factor() * (row_height - glyph.size.y);
+            glyph.pos.y = cursor_y
+                + glyph.font_impl_ascent
+                + format.valign.to_factor() * (row_height - glyph.size.y);
 
             glyph.pos.y = point_scale.round_to_pixel(glyph.pos.y);
         }
diff --git a/crates/epaint/src/text/text_layout_types.rs b/crates/epaint/src/text/text_layout_types.rs
index 5872844f9..22361d10d 100644
--- a/crates/epaint/src/text/text_layout_types.rs
+++ b/crates/epaint/src/text/text_layout_types.rs
@@ -608,8 +608,11 @@ pub struct Glyph {
     /// Logical position: pos.y is the same for all chars of the same [`TextFormat`].
     pub pos: Pos2,
 
-    /// `ascent` value from the font
-    pub ascent: f32,
+    /// `ascent` value from the `Font`
+    pub font_ascent: f32,
+
+    /// `ascent` value from the `FontImpl`
+    pub font_impl_ascent: f32,
 
     /// Advance width and line height.
     ///
@@ -631,7 +634,7 @@ impl Glyph {
     /// Same y range for all characters with the same [`TextFormat`].
     #[inline]
     pub fn logical_rect(&self) -> Rect {
-        Rect::from_min_size(self.pos - vec2(0.0, self.ascent), self.size)
+        Rect::from_min_size(self.pos - vec2(0.0, self.font_ascent), self.size)
     }
 }